The invention relates to an apparatus for the shaping and compacting of absorbent pads for absorbing body fluid which consist of a plurality of part layers and which is intended for articles of hygiene, especially for the production of body-shaped absorbent pads for disposable baby napkins and disposable adult napkins, sanitary towels, insert slips and the like.
There are known apparatuses for the production of articles of hygiene, in which a web of material resembling an absorbent pad is guided continuously through a severing device, and the lateral edge regions of the web of material are thereby severed to the desired shape, for example for shaping the leg portions into a bobbin-like form for disposable napkins. Severing is carried out by punching out or sawing or by means of water-jet or air-jet cutting in an additional device, and at the same time hard edges can be obtained at the cutting points as a result of the compacting of the flocks. In continuous production, a severing device of this type can give rise to faults, and material waste is unavoidable, thus entailing an undesirable outlay and increasing the operating costs.
So that the absorbent pads do not have to be machined by shaping cutting during production, for example German Offenlegungsschrift 3,710,055 provides an apparatus for the continuous production of sanitary towels, in which a plurality of flock-depositing stations arranged over the circumference of a rotatable suction drum and having an air-permeable bottom are used. Each depositing point is equipped with a tool set which is mounted firmly on the suction drum and which comprises at least one shaping-shoe/flock-template unit, a press ram and a welding and, if appropriate, severing tool.
With such an arrangement of the individual processing devices, because of the complicated tool sets connected to lifting motors via lifting rods a conversion of the apparatus to other articles of hygiene demands a large amount of time and is possible only to a restricted extent, with the result that apparatuses of this type are only ever used as single-purpose machines.
A further disadvantage is that the feeding of superabsorbent agents from the periphery of the suction drum into the absorbent pads cannot be achieved to the best possible degree. The superabsorbent agent is introduced into a particular shaping recess and then transferred from this onto the flock web. This solution does not always ensure an exact filling of the shaping recesses, and therefore the quantity of this agent can fluctuate in the articles produced.
Another embodiment of an apparatus for the production of absorbent pads for absorbing body fluid is known from DE 3,413,925 A1. The apparatus consists of two so-called flock applicators of identical design, each of the two flock applicators being designed as a suction cylinder which has shaping recesses and which forms the so-called flock wheel. A first part layer of the absorbent pad to be produced is sucked onto the first flock wheel, and a second part layer is sucked onto the second flock wheel. By means of a transfer roller, the part layers produced on the first flock wheel are applied to the part layers produced on the second flock wheel. A further transfer roller lifts off the finished absorbent pads from the second flock wheel and transfers them to a further-processing machine by means of a suction belt. A possible addition of a superabsorbent agent can be provided between the two part layers forming the absorbent pads.
The apparatus is a single-purpose machine which is suitable only for a few articles of hygiene of similar design, but a more comprehensive conversion of the apparatus for different articles is hardly expedient. Another disadvantage is that only absorbent pads consisting of two part layers can be produced, because it is scarcely possible to connect further flock wheels and transfer rollers, especially where part layers of differing size are concerned.
A thermal compacting device which can be built into a continuous production line and is intended for an absorbent-pad web treated with superabsorbent agent and which makes use of a hot-air throughflow principle is likewise known. The air throughflow warms through on both sides, on two perforated drums, the absorbent pads connected in the form of webs and, if appropriate, equipped with covering webs on both sides, so that a heating to the compacting temperature takes place. The cellular/synthetic pulp mixture is compacted thermally, and at the same time the superabsorbent agent is fixed in at predetermined points of the absorbent pad.
This apparatus is unsuitable for the thermal compacting of individual absorbent pads conveyable at a distance in succession and, if appropriate, also next to one another or covered with a covering web on only one side.